Cognitive Task Analysis of En Route Air Traffic Control: Model Extension and Validation.

Phase II of a project extended data collection and analytic procedures to develop a model of expertise and skill development for en route air traffic control (ATC). New data were collected by recording the Dynamic Simulator (DYSIM) performance of five experts with a work overload problem. Expert controllers were interviewed in depth for mental model elaboration and validation. Federal Aviation Administration data regarding operational errors were analyzed. An extended literature review was conducted to integrate findings with existing literature. An elaborated and refined mental model and task decomposition were developed. The structure of the mental model implied both a conceptual framework used by the controller for organizing ATC knowledge and a strategy for applying the knowledge in job conduct. The task decomposition resulted in a listing and validation of 12 tasks. The analysis of strategy usage showed that experts tended to use fewer strategies, a greater variety of different strategies, more workload management strategies, and strategy usage that varied with context. A working model of interrelationships among key ATC constructs was developed. A revised listing of critical cues of work overload indicated that participants viewed anxiety and communication errors as being the most important cues that an overload situation was developing. Training implications were identified in the areas of instructional content, sequencing, media delivery, and training environment. (Appendixes include the following: a list of 57 references, a glossary of terms and acronyms, a glossary of strategies, a validation study timeline, strategy listings and validation interviews, retrospective protocols of DYSIM overload problem solving, a work overload questionnaire, and an error listing for DYSIM overload problem solving.) (YLB)